Crypto glossary
Portfolio rebalancing
Portfolio rebalancing is selling assets that grew beyond their target weight and buying those that fell behind, on a set calendar or when bands are crossed.
Over time, price moves pull a portfolio away from its plan. If bitcoin doubles while altcoins stagnate, a 50/50 split might become 70/30. Rebalancing restores the target by trimming winners and adding to laggards, either on a calendar (monthly, quarterly) or when an asset drifts past a threshold such as five percentage points.
In a market as volatile as crypto, rebalancing turns allocation rules into discipline: it forces some profit-taking in euphoric phases and buying during slumps. Some index tokens, vault strategies and robo-style apps rebalance automatically, and investors adding new money can steer contributions to underweight assets instead of selling.
Every sale can be a taxable event, so frequent rebalancing in Spain or elsewhere may crystallise gains and create paperwork. Trading fees, spreads and on-chain gas add up, and in strong trends systematic rebalancing can cut exposure to the best performer too early. Threshold bands that are too narrow trigger needless trades.
Example
A portfolio set at 70% BTC and 30% ETH drifts to 80/20 after a bitcoin rally, so the investor sells some BTC for ETH to return to the original weights.